We have already discussed what CGI is. CGI is a way to transmit data with the help of server. We have also discussed in detail how the CGI program works. As a novice, you may not have detailed knowledge about the application of CGI program. Perhaps, you have heard from people, who deal with web page about this program and the script of CGI. At first it may sound little strange to you and you may not understand what exactly they are talking of. To express it more precisely we can say that CGI is nothing but a connection between   web sever and the web page. Let us make it clear. The web page itself can not interact with the user directly. Before the invention of Java script, there was no scope of interpreting the reaction of the reader without taking the help of the server. Therefore to produce interactive programs on the web pages we need the help of the CGI or the common gateway interface. It is very important for a user of CGI to know some bare facts about CGI. Unless you understand and remember them, you may not able to know this CGI properly. Here you may raise a question, what are the things to remember about CGI? Now let us discuss about it.

Firstly, you should remember that CGI itself is not a program. It is   barely an interface between the browser and the server. That means there is a necessity to establish a close link between the web page and the server, which helps to run the program. Secondly, you may find many hosts who provide free service will not allow accessing CGI with the server. In such a situation, you must contact the host. Lastly, you should remember that the script that runs on your web server is usable for CGI program. You can use Perl as CGI script. There are also other alternative.